The invention relates to a rail fastener comprising an anchoring shaft for securing the rail fastener in a fastening base (e.g., a railroad tie) which supports a rail, and a head which is integrally molded on the anchoring shaft and is configured to receive a torque for the purpose of screwing the anchoring shaft into the fastening base. Furthermore, the invention relates to a rail fastening arrangement having such a rail fastener.
Rails for trains are laid on railroad ties. The rails themselves have a mounting flange which sits on the top side of the railroad tie. The rails are fastened to the railroad ties by means of rail fasteners. The rail fasteners are secured by an anchoring shaft in the railroad tie next to the rail. A rail hold-down spring serves to hold the rail, the spring being bent essentially in a U shape with its section connecting the two legs protruding beyond the mounting flange of the rail opposite the rail head and being braced against the flange by the rail fastener. Such a rail fastener comprises the anchoring shaft mentioned above and a head integrally mounted thereon. The head is designed as a polygonal head, so that a torque can be applied by a tool to secure it. A collar is formed on the bottom side of the head to provide a sufficiently protruding edge, which acts on the top side of the leg of the hold-down spring. A flexible rail fastening is necessary to equalize movement between the rail and the railroad tie. The hold-down spring serves this purpose. With this type of rail fastener already known in the art, the fastener is secured by screwing the anchoring shaft into the fastening base, and at the same time the hold-down spring is stressed against the mounting flange of the rail. If the railroad ties are precast concrete components, they are equipped with dowels inserted into prefabricated fastening boreholes, so that the anchoring shaft engages in such a dowel for securing it. The dowels used are preferably plastic dowels.
Such rail fasteners are in use throughout the world. However, because of movement occurring between the rail and the railroad tie, the rail fasteners have the disadvantage of requiring to be inspected at regular intervals with respect to how well the rail is anchored. It is often necessary to retighten the rail fastener. To ensure safe railway operation, regular inspections of the rail fastening must usually be performed several times a year.